Direct Drive to Diff E Revo Build

[sikeston34m]

I'm trying something different here. I thought I would share this with you guys. I'm sure I'll be learning alot through out this build. With the success I've had with outrunners and the E maxx, I couldn't resist doing this.

I found the weakest link in the E maxx to be the transmission, even with upgraded parts just short of aluminum case and all steel gears. SO........let's eliminate the transmission altogether and go with the Revo. Less parts to break, we've saved some weight, and hopefully this will be tough!

The Motor I've chosen is the AXI 4130/20. It's stator is 41mm in diameter and is 30mm long. It is a hoss of a motor. In Airplane use, it can swing a 20" prop directly and fly an airplane that weighs 15.4 pounds! Let's see how well it can "fly" a 9 or 10 pound Revo.

The Motor weighs 409 grams. It is 50mm in diameter and 65mm long. It can be fed with up to 8 Series Lipo. It can handle 40amps continously at around 30 volts, and 55 amp bursts for up to 60 seconds(almost 1900 watts!). The 4130/20 wind is 305kv. Axi also has a 4130/16 that is 385kv. I chose the lower kv for the starting torque. I fear cogging on startup, this will help. If cogging isn't an issue, I can step up to the 385kv version.

To help with heat issues, a cooling fin assembly has been added to the endbell. In testing on 4S Lipo, It really moves a good amount of air.

I'm going to go with the stock diff ratio for starters. If cogging is a problem, I will order the RCM buggy gears. They are offered in 4:1 and 4.3:1 ratios. The 4.3:1 ratio is VERY close to the E maxx in 2nd gear. This would require spinning the drive shaft much faster to get the same top speeds though.

The motor shaft is a STOCK Revo tranny output shaft. I simply removed the steel hump from the middle to create a smooth 6mm shaft that is ready to accept the Revo driveshafts. The length worked out perfect with 1 or 2 mm to spare.

I'm not done with it yet, but I will update as the build progresses. Let me know your thoughts.

Here's a few pictures of the Motor mount/lower skid plate.